In order to optimize the surface flatness and roughness of borosilicate glass, this study employs the chemical mechanical polishing technology(CMP) for the surface flattening of borosilicate glass. The polishing characteristics of the sample has been studied by adjusting the process parameters of CMP, including the polishing time, the rotate speed of polishing disk, the rate of polishing liquid flow, and the polishing pressure. And finally, the surface flattening treatment of the sample was realized in the study. The results show that when the process parameters varied, the surface peak-valley value and surface roughness value of the glass shared the similar trend. As the polishing time increased, they decreased rapidly and then gradually stabilized. During the increase of the rotate speed of polishing disk, the rate of polishing liquid flow, and the polishing pressure, they showed a trend of firstly decreasing and then increasing.
The stock removal uniformity in planetary double-sided polishing process has an important influence on the optical materials surface quality. The velocity equation is set up through the kinematical analysis of double-sided polishing process, which refers to any point of the workpieces relative to the pad, and then a quantitative evaluation method of stock removal uniformity is simulated, and finally the optimal parameters of stock removal uniformity are obtained. As the results shown, when the radius ratio between the sun gear and ring gear is equal or greater than 0.2, the parameters m and n fit the equation: n=2.33m-0.06, the optimal stock removal uniformity is obtained.
Microchannel plate (MCP) is an important charged-particle electronic multiplier, whose surface roughness is one of the vital factors of high-performance multiplication. A chemical-mechanical polishing (CMP) is a planarization process assisted by chemical reactions to remove surface materials and improve surface smoothness. In this paper, atomic force microscopy (AFM) was applied to investigate the surface roughness of the MCP wafers by chemical-mechanical polishing. After chemical-mechanical polishing, the global surface roughness increased from 8.33 nm into 9.01 nm, which was contrary to the conventional chemical-mechanical polishing results. Using the surface partitioning analysis, we confirmed that the escalated global surface roughness was related to the raised surface roughness of the acid-soluble core glass (from 2.35 nm rise to 3.07 nm after CMP), which occupied more than 60% area of the MCP wafer. Moreover, the surface roughness of the etching-resistance cladding glass was notably dropped after CMP (from 6.48 nm decreased to 4.84 nm). Thus, CMP was a benefit to improve the surface finishing of the MCP multiplier despite the global surface roughness increasing after that.
Micro-nano project by studying the micro channel plate surface micro convex particle sizes can produce a phenomenon of point discharge which causes the field emission, and particles on the surface on the micro channel plate mechanism, then through metallographic microscope classification and testing for different particle morphology, finally three kinds of particle preparation is be determined. Through the study, by water to remove the ultrasonic repeatedly can get rid of polishing powder residue. And acid etching process of silica particles by adding alkali ultrasonic frequency and the use of high frequency ultrasound alternately can be completely removed. Then through evaporation before increasing ion bombardment can effectively control the micro convex particles which is produced after evaporation electrod. Through the study, by water to remove the ultrasonic repeatedly can get rid of polishing powder residue. And acid etching process of silica particles by adding alkali ultrasonic frequency and the use of high frequency ultrasound alternately can be completely removed. Then through evaporation before increasing ion bombardment can effectively control the micro convex particles which is produced after evaporation electrod.
Through the influence of the temperature, concentration, acid type and acid dissolution time of the acid solution on the acid etching speed of the multi-fiber and the surface quality after acid etching, the acid dissolution mechanism of the acid solution flexible optical fiber image bundle is discussed. The weight loss method was used to test the acid dissolution rate of different acid-soluble glasses, combined with the breakage of the multi-fiber after acid dissolution, to study the effect of acid-soluble glass on the image quality of the flexible optical fiber image bundle. The experimental results show that using a suitable acid solution, a suitable acid solution concentration, a suitable temperature and a reasonable acid dissolution time has obvious effects on reducing the broken wire rate of the flexible optical fiber image bundle and improving the image transmission quality.
The anti-vignetting glass (AVG) is the key material for super-second and third-generation low-light image intensifiers. With the development of low-light night vision technology, the requirements of high precision and low damage are put forward to AVG. However, traditional measurement methods, such as vernier calipers, micrometers, dial indicators, etc., are all contact measurement, which will inevitably cause damage to AVG during the measurement process. They cannot meet the technical requirements for low damage. Non-contact measurement technology is a non-destructive testing method that realizes the geometric measurement of AVG by writing measurement programs and setting measurement parameters. However, due to the special structure of AVG, the non-contact measurement technology has measurement errors and cannot meet the high-precision measurement requirements. In this paper systematically analyzes the causes of errors in non-contact measurement technology by studying the characteristics of the light source, the difference in light intensity, and the way of grabbing contour edges. Through the error correction technology, the error of the non-contact measurement technology is eliminated, the AVG high-precision and low-damage non-destructive testing is realized.
Microchannel plate (MCP) is an important compact two-dimension multiplier for parallel multiplication of charged particles. With the advantages of high temporal resolution, high spatial resolution, high electron gain and compact structure, microchannel plate has become an important potential readout device for cryogenic quantum computing, such as the quantum computation based on floating electrons of liquid helium surface. For the sake of ultra-fast reading, it requires the signal readout time is less than 10-5 s at a temperature lower than 30K in the cryogenic quantum computing. However, the bulk resistance of MCP multiplier became giant at cryogenic temperature for the property of huge negative temperature coefficient of resistance, almost 105 Gohm at 20K~30K, resulting in a readout time of 10-2 -1s at cryogenic temperature, which was one of the major bottlenecks for the application of MCPs in the cryogenic quantum computing. In this paper, the bulk resistance of MCPs in two different bismuth contents (1at%, 2.4at%) under the same hydrogen reduction temperatures (730K) were present as the surrounding temperature controlled from 300K to 20K. The cryogenic bulk resistance of MCP was only decreased into 24% with the increase bismuth content from 1at% to 2.4at%, while thereof the normal bulk resistance was decline into 5%. The normal bulk resistance reduced only in the manner of improving the conductivity of conductive layer, could also increase the temperature-resistance sensitivity of MCP, leading an even greater temperature coefficient of resistance, which deteriorated the stability of readout in the cryogenic quantum computing.
For reducing the self-excited oscillation of end-pumped laser, the laser properties of the end-pumped Nd:YAG Q-switched laser is investigated with different Nd3+ ion doping concentration. The experiment results indicate that the output energy of the end-pumped Nd:YAG Q-switched laser is saturated when the pump energy is greater than 467mJ with 0.6% Nd3+ ion doping concentration, and the maximum output energy of 62.9mJ is generated under the pump energy of 498mJ, corresponding to the optical conversion efficiency of 12.6%. When the Nd3+ ion doping concentration decreases to 0.4%, the output energy of the end-pumped Nd:YAG Q-switched laser increases continuously with increasing pumping energy, the output energy is up to 64.7mJ under the pump energy of 498mJ, corresponding to the optical conversion efficiency of 13.0%, and no saturation occurs. By optimizing the structure parameters of the pump system, a 82.1mJ 10ns 1064nm laser is obtained under the pump energy of 527mJ, corresponding to the optical conversion efficiency of 15.6%. In view of the saturation of output energy in the end-pumped Nd:YAG Q-switched laser, Nd3+ ion doping concentration adjustment is carried out to reduce the pump end-face gain of laser medium, the self-excited oscillation can be effectively suppressed, an effective technical means for obtaining high-energy end-pumped Q-switched laser output is provided.
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